Electrical conductivity of pure carbon nanotube yarns

The porosity of multi-walled carbon nanotube yarns can be varied over a wide range by adjusting the yarn construction, resulting in a dramatic change in yarn electrical conductivity. When the yarn electrical conductivity is converted into specific conductivity, its value remains approximately constant irrespective of the changes in yarn construction and porosity. The process of carbon nanotube yarn production involves two key steps, the formation of a network of carbon nanotube bundles spliced together by the entanglement of individual nanotubes and the compaction of the network into a cylindrical yarn. The splices formed from entangled individual nanotubes play a much greater role in electrical conduction than the cross-over contact formed between CNT bundles by compaction during spinning.